1. Field of the Invention
This invention relates to cryogenic structures particularly those of durable plastics.
2. The Prior Art
Traditional cryogenic structural materials are usually metallic, which impose severe weight penalties on the design employed.
Graphite/epoxy composite structures have been tried but have been found not suitable for cryogenic applications due to microcracking and the need to incorporate a metallic liner. The liner and its composite structure however, usually have different coefficients of thermal expansion resulting in disbonding of the liner and its composite structure.
For a disclosure of a lined cryogenic tank, see for example USSIR H943 to Garvey and the references cited therein.
There is a need however, to provide a cryogenic structure, including a vessel or tank, that overcomes the above prior art shortcomings.
There has now been discovered the use of suitable materials for cryogenic structures that do not require a metallic liner and provide a more durable cryogenic structure at often reduced costs.